ΔE 6.3, close: similar, with a visible difference side by side. Dark Mustard Khaki is a little lighter than IDF Modern Grey.
Usually, if you are not matching paint already on the model. Close match (ΔE 6). Dark Mustard Khaki is a little lighter than IDF Modern Grey.
The same difference applies the other way round: IDF Modern Grey is a little darker.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See IDF Modern Grey on the colour wheel See Dark Mustard Khaki on the colour wheel
All matches: IDF Modern Grey equivalents · Dark Mustard Khaki equivalents